Comment # 4 on bug 768568 from Bernhard Wiedemann

still seing this in current Factory
(though it can not be triggered with systemd alsa restarts)

(gdb) bt
#0  0x00007f7045e23054 in vnc_connection_server_message (conn=0xdaa370)
    at vncconnection.c:3190
#1  vnc_connection_coroutine (opaque=<optimized out>) at vncconnection.c:5192
#2  0x00007f7045e2639b in coroutine_trampoline (cc=0xda6810)
    at coroutine_ucontext.c:55
#3  0x00007f7044042be0 in ?? () from /lib64/libc.so.6